Low chamfer angled torque tube end fitting with elongated overflow groove

Abstract

A method of forming a torque-transmitting coupling ( 193 ) includes forming at least one fitting ( 192 ) having a tube conforming area ( 200 ). The forming area ( 200 ) includes a material overflow groove ( 194 ) and multiple flat surfaces ( 202 ). The forming area ( 200 ) has an associated tube arc length that is approximately equal in length to a formed area length of the flat surfaces ( 202 ) with the elongated overflow groove ( 194 ). An elongated tube ( 190 ) is procured. The elongated tube ( 190 ) is formed onto the tube conforming area ( 200 ) to form the torque-transmitting coupling ( 193 ).

1. A method of forming a torque-transmitting coupling comprising:
 forming at least one fitting having at least one elongated tube conforming area, said at least one elongated tube conforming area forming at least one chamfer surface and having at least one overflow groove and a plurality of flat surfaces, said at least one elongated tube conforming area having at least one associated tube arc length that is approximately equal in length to a formed area length of said plurality of flat surfaces with said at least one overflow groove, wherein forming at least one chamfer surface comprises forming an upper surface, a lower surface, and a chamfer transitional surface that transitions between said upper surface and said lower surface and has a chamfer angle of approximately 20° to 25° relative to said lower surface; 
 forming a tube onto said at least one fitting; 
 procuring said tube; and 
 forming an end portion of said tube onto said at least one elongated tube conforming area to form the torque-transmitting coupling. 
 
   
   
     2. A method as in  claim 1  wherein said at least one associated tube arc length is approximately equal in length to said formed area length ±0.5%. 
   
   
     3. A method as in  claim 1  wherein said at least one fitting is formed such that said at least one associated tube arc length and said formed area length are predetermined such that said tube is neither in tension nor in compression over said at least one elongated tube conforming area. 
   
   
     4. A method as in  claim 1  wherein said formed area length is approximately equal to a sum of an overflow groove arc length and twice a width of said plurality of flat surfaces. 
   
   
     5. A method as in  claim 1  wherein said tube comprises an inner surface with a plurality of fitting contact points, said at least one associated tube arc length defined as a distance along said inner surface between sequential fitting contact points over at least one forming surface area of said at least one fitting. 
   
   
     6. A method as in  claim 5  wherein said formed area length is a distance between sequential fitting contact points on said at least one fitting over said at least one forming surface area. 
   
   
     7. A method as in  claim 1  wherein forming at least one fitting comprises forming an arced surface between said chamfer transitional surface and said upper surface that has a significantly sized radius. 
   
   
     8. A method as in  claim 1  further comprising corrosive inhibit treating said tube. 
   
   
     9. A method as in  claim 8  wherein corrosive inhibit treating said tube comprises applying an alodine film to said tube. 
   
   
     10. A method as in  claim 1  wherein forming said end portion of said tube comprises electromagnetically forming said end portion of said tube onto said at least one elongated tube conforming area. 
   
   
     11. A method as in  claim 1  further comprising aging said tube. 
   
   
     12. A method as in  claim 1  wherein said at least one fitting is formed in a polygon shape having a plurality of polygon surfaces comprising said plurality of flat surfaces and said at least one overflow groove. 
   
   
     13. A method as in  claim 1 , wherein said chamfer angle is approximately 20° relative to said lower surface. 
   
   
     14. A method of forming a torque tube comprising:
 forming at least one fitting having at least one elongated tube fusing area comprising forming at least one chamfer surface and an associated tube arc length that is approximately equal in length to a formed area length of a plurality of flat surfaces and at least one elongated overflow groove, wherein forming at least one chamfer surface comprises forming an upper surface, a lower surface, and a chamfer transitional surface that transitions between said upper surface and said lower surface and has a chamfer angle of approximately 20° to 25° relative to said lower surface; 
 procuring an elongated tube; and 
 forming an end portion of said elongated tube onto said elongated tube fusing area to form a torque-transmitting coupling. 
 
   
   
     15. A method as in  claim 14  wherein said at least one associated tube arc length is approximately equal in length to said formed area length ±0.5%. 
   
   
     16. A method as in  claim 14  wherein said at least one fitting is formed such that said at least one associated tube arc length and said formed area length are predetermined so that said elongated tube is neither in tension nor in compression over said at least one elongated tube conforming area. 
   
   
     17. A method as in  claim 14  wherein said formed area length is approximately equal to a sum of an overflow groove arc length and twice a width of said plurality of flat surfaces. 
   
   
     18. A method as in  claim 14  wherein said elongated tube comprises an inner surface with a plurality of fitting contact points, said at least one associated tube arc length defined as a distance along said inner surface between sequential fitting contact points over at least one formed area length of said at least one fitting. 
   
   
     19. A method as in  claim 18  wherein said at least one formed area length is a distance between sequential fitting contact points on said at least one fitting over said at least one elongated tube fusing area. 
   
   
     20. A method as in  claim 14  wherein forming at least one fitting comprises forming an arced surface between said chamfer transitional surface and said upper surface that has a significantly sized radius. 
   
   
     21. A method as in  claim 14  further comprising corrosive inhibit treating said elongated tube. 
   
   
     22. A method as in  claim 21  wherein corrosive inhibit treating said elongated tube comprising applying an alodine film to said elongated tube. 
   
   
     23. A method as in  claim 14  wherein forming an elongated tube comprises electromagnetically forming said end portion of said elongated tube over said at least one fitting. 
   
   
     24. A method as in  claim 14  further comprising artificially aging said elongated tube. 
   
   
     25. A torque tube formed according to the method of  claim 14 . 
   
   
     26. A torque tube comprising:
 at least one fitting having at least one elongated tube fusing area comprising:
 at least one chamfer surface; 
 at least one elongated overflow groove; and 
 a plurality of flat surfaces, 
 
 said at least one elongated tube fusing area having at least one associated tube arc length that is approximately equal in length to a formed area length of said plurality of flat surfaces with said at least one elongated overflow groove; and an elongated tube formed onto said elongated tube fusing area, wherein said at least one chamfer surface comprises: 
 at least one upper surface; 
 at least one lower surface; and 
 at least one chamfer transitional surface forming said at least one chamfer surface with said at least one upper surface and said at least one lower surface and having a chamfer angle of approximately 20° to 25° relative to said at least one lower surface. 
 
   
   
     27. A torque tube as in  claim 26  wherein said at least one associated tube arc length is approximately equal in length to said formed area length ±0.5%. 
   
   
     28. A torque tube as in  claim 26  wherein said at least one fitting is formed such that said at least one associated tube arc length and said formed area length are predetermined such that said elongated tube is neither in tension nor in compression over said at least one elongated tube fusing area. 
   
   
     29. A torque tube as in  claim 26  wherein said formed area length is approximately equal to a sum of an overflow groove arc length and twice a width of said plurality of flat surfaces. 
   
   
     30. A torque tube as in  claim 26  wherein said elongated tube comprises an inner surface with a plurality of fitting contact points, said at least one associated tube arc length defined as a distance along said inner surface between sequential fitting contact points over said at least one elongated tube fusing area. 
   
   
     31. A torque tube as in  claim 30  wherein said formed area length is a distance between sequential fitting contact points on said at least one fitting over said at least one elongated tube fusing area. 
   
   
     32. A torque tube as in  claim 26  further comprising an arced surface between said at least one chamfer transitional surface and said at least one upper surface that has a significantly sized radius. 
   
   
     33. A torque tube as in  claim 26  wherein said elongated tube is electromagnetically formed onto said at least one fitting. 
   
   
     34. A torque tube as in  claim 26  wherein said elongated tube has at least one corrosive inhibiting layer. 
   
   
     35. A torque tube as in  claim 34  wherein said at least one corrosive inhibiting layer comprises an alodine layer and a paint layer. 
   
   
     36. A torque tube as in  claim 26  wherein said elongated tube is aged to have a T-81 temper. 
   
   
     37. A vehicle comprising:
 at least one torque tube comprising; 
 at least one fitting having at least one elongated tube conforming area comprising: 
 at least one chamfer surface; comprising; 
 at least one upper surface; 
 at least one lower surface; and 
 at least one chamfer transitional surface forming said at least one chamfer surface with said at least one upper surface and said at least one lower surface and having a chamfer angle of approximately 20° to 25° relative to said at least one lower surface; 
 at least one elongated overflow groove; and 
 a plurality of flat surfaces, 
 said at least one elongated tube conforming area having at least one associated tube arc length that is approximately equal in length to a formed area length of said plurality of flat surfaces with said at least one elongated overflow groove; and an elongated tube formed onto said at least one elongated tube conforming area, wherein said at least one elongated tube comprises an inner surface, said at least one associated tube arc length defined as a distance along said inner surface between sequential fitting contact points over said at least one elongated tube conforming area.